<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script>
				    var BMI = 23;
				    var result = "";
				    if(BMI < 20){
				        result = "体重过轻";
				    }else if(BMI >= 20 && BMI < 25){
				        result = "体重适中";
				    }else if(BMI >= 25 && BMI < 30){
				        result = "体重过重";
				    }else if(BMI >= 30 && BMI < 35){
				        result = "肥胖";
				    }else{
				        result = "非常肥胖";
				    }
				    document.write("BMI："+BMI);
				    document.write("<br>结果："+result);
		        </script>
	</body>
</html>
